Method of manufacturing an interlocked, “flush-to-front,” injection molded border and glass sheet

ABSTRACT

The method of the present invention is performed by providing a glass sheet having first and second opposite surfaces merging with each other along a peripheral ground angled surface setting-off with the glass sheet first surface an included angle substantially greater than normal. The glass sheet is placed in a mold having opposing cavity portions which collectively define a cavity including a peripheral edge cavity portion defined in part by a cavity defining surface which lies in the plane of the glass sheet first surface when the mold is closed. The mold is then closed such that the cavity defining surface and the glass sheet round angled surface set-off and angled complementary to the included angle and with the glass sheet per surface abutting the cavity defining surface inboard of the glass sheet ground angled surface. Polymeric/copolymeric synthetic plastic material is injected into the peripheral cavity portion to completely encapsulate the glass sheet periphery with a border, frame or encapsulation having a first exterior surface coplanar with the glass sheet first surface whereby the latter two surfaces are “flush-to-front” and the glass sheet periphery is in undercut interlocked relationship with the injection molded border.

BACKGROUND OF THE INVENTION

Heretofore it has been common to provide a glass sheet with a border forsubsequent utilization as a shelf, a cooktop panel or the like. If theborder is an injection molded polymer/copolymeric encapsulation, it iscommon to utilize a bonding agent to affix the injection moldedpolymeric/copolymeric frame or border to a peripheral edge of the glasssheet. In U.S. Pat. No. 5,785,047 granted to the assignee of the presentinvention on Jul. 28, 1998, there is disclosed a cooktop, hob top or thelike which includes an injection molded encapsulation surrounding aperipheral edge of a cooktop panel with peripheral surfaces of thelatter having a primer applied thereto, such as Chemlok AP-134 one-coatprimer and/or Chemlok EP 6962-50A/P primer, each manufactured by LordCorporation of 2000 West Grand View Blvd., P.O. Box 10038, Erie, Pa.16514-10038. The primer augments the adhesion between the peripheraledge of the Ceran®, glass or equivalent panel and the encapsulation,frame or border which preferably is Santoprene® manufactured by AdvancedElastomer Systems L.P.

In order to achieve ease of cleaning and maintenance, uppermost surfacesof the cooktop, the injection molded encapsulation or border and anassociated trim piece are substantially flush. However, utilization ofprimer, adhesive or an equivalent bonding agent to affix an extrudedframe to the glass or Ceran® panel presents numerous problems, bothduring manufacture and when in use. Obviously, the application of aprimer or a bonding agent necessitates additional cost for the materialutilized and the additional costs involved in applying the primercarefully and selectively to the periphery of the Ceran® or glass panel.Delamination can also occur in use, particularly upon primer breakdownand attendant debonding of the frame and glass panel.

In lieu of injection molding a frame to a periphery of a glass sheet, itis also common to utilize a multi-part plastic frame of the typedisclosed in U.S. Pat. No. 4,934,541. The multi-part plastic framerequires the separate manufacture of two frame members which are thenseparately assembled and united with a glass panel by ultrasonicwelding. This process avoids delamination when primer breaks down and/orloses its bonding efficacy, particularly during long term use underadverse conditions. However, the costs of manufacturing multi framemembers and uniting the same through ultrasonic welding is also costprohibitive.

Each of these two approaches present more problems than solutions. Theinjection molding operation presents an aesthetically pleasing product,yet the costs of primer and its application is undesirably prohibitive,particularly when delamination can occur either because of ineffectivepriming during manufacture and/or the existence of gaps and voids whichcan be attacked when in use resulting in delamination. Ultrasonicwelding precludes delamination, but multi-step manufacturing iscost-prohibitive. Ideally, the best of both worlds would be a“flush-to-front” interlocked, injection molded border and glass sheetlacking primer or bonding material which is relatively strong, can beabused to a considerable extent absent deterioration, is aestheticallypleasing, can be readily cleaned, and can be manufactured at minimumcosts.

SUMMARY OF THE INVENTION

In keeping with the foregoing, a primary object of the present inventionis to provide a novel method of manufacturing a frame, border orencapsulation along a peripheral edge portion of an article,particularly a glass panel, and simultaneously create therebetween aninterlock, absent the utilization of a primer or bonding agent, while atthe same time creating an aesthetic “flush-to-front” appearance.

The method of the present invention is performed by providing a glasssheet having first and second opposite surfaces merging with each otheralong a peripheral ground angled surface setting-off with the glasssheet first surface an included angle substantially greater than normal.The glass sheet is placed in a mold having opposing cavity portionswhich collectively define a cavity including a peripheral edge cavityportion defined in part by a cavity defining surface which lies in theplane of the glass sheet first surface when the mold is closed. The moldis then closed such that the cavity defining surface and the glass sheetground angled surface set-off an angle complementary to the includedangle and with the glass sheet first surface abutting the cavitydefining surface inboard of the glass sheet ground angled surface.Polymeric/copolymeric synthetic plastic material is injected into theperipheral cavity portion to completely encapsulate the glass sheetperiphery with a border, frame or encapsulation having a first exteriorsurface coplanar with the glass sheet first surface, whereby the lattertwo surfaces are “flush-to-front” and the glass sheet periphery is inundercut interlocked relationship with the injection molded border.

The method thus described is utilized for manufacturing numerousproducts, but the present invention is particularly directed to theutilization of the framed glass sheet as a computer screen or a computerglare filter, though the method is equally applicable to forming cooktops, refrigerator shelves, refrigerator doors, and the like.

With the above and other objects in view that will hereinafter appear,the nature of the invention will be more clearly understood by referenceto the following detailed description, the appended claims and theseveral views illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of a novel article manufactured inaccordance with this invention, and illustrates a glass sheet having aperipheral edge portion totally encapsulated by an in situ injectionmolded polymeric/copolymeric plastic material frame or border.

FIG. 2 is an enlarged fragmentary vertical cross-sectional view takengenerally along line 2—2 of FIG. 1 and illustrates an undercutinterlocked juncture between a peripheral edge of the glass sheet andthe injection molded frame, as well as the “flush-to-front” exteriorthereof.

FIG. 3 is a vertical cross-sectional view taken through an injectionmold of the present invention, and illustrates upper and lower moldbodies in their open position with each defining a cavity portion, whichin the closed position of the mold bodies defines a mold cavity.

FIG. 4 is a vertical cross-sectional view of the mold of FIG. 3, andillustrates a glass sheet positioned with a peripheral edge thereof inoverlying relationship to a peripheral upwardly opening cavity portionof the lower mold body.

FIG. 5 is a vertical cross-sectional view of the mold of FIGS. 3 and 4,and illustrates the mold bodies in their closed position with an upperor first surface of the glass sheet lying in a plane coplanar to asurface of the upper mold body defining a portion of the cavity thereof.

FIG. 6 is a vertical cross-sectional view of the mold, and illustratespolymeric/copolymeric synthetic plastic material injected into the moldcavity and encapsulating a periphery of the glass sheet to form anundercut interlock therewith while forming a “flush-to-front” exteriorsurface.

FIG. 7 is a vertical cross-sectional view of the mold of FIGS. 3 through6, and illustrates the mold bodies moved to an open position incident tothe removal therefrom of the bordered, framed or encapsulated glasssheet.

FIG. 8 is a perspective view of another article manufactured inaccordance with this invention, and illustrates a refrigerator crisperdrawer which includes a glass sheet in a front wall thereof completelyencapsulated by a border or frame created during the in situ injectionmolding of the crisper drawer.

FIG. 9 is a slightly enlarged vertical cross-sectional view takengenerally along line 9—9 of FIG. 8, and illustrates the undercutinterlocked juncture between a periphery of the glass sheet and theborder or frame of the front wall of the crisper drawer.

FIG. 10 is a vertical cross-sectional view through a mold, andillustrates two mold bodies in the closed position thereof defining acavity in which the drawer is injection molded and simultaneouslytherewith the glass sheet is interlocked in “flush-to-front”relationship to the border of a front wall of the drawer.

FIG. 11 is a vertical cross-sectional view of the mold of FIG. 10, andillustrates upper and lower mold bodies thereof moved to an openedposition to facilitate the removal of the drawer therefrom.

FIG. 12 is a fragmentary enlarged view, and illustrates details of theglass-to-border interlock of FIGS. 8 through 10 of the drawings.

FIG. 13 is an enlarged fragmentary cross-sectional view similar to FIG.2, and illustrates another undercut interlocked junction between aperipheral edge of a glass sheet and an injection molded encapsulationor frame, including the “flush-to-front” exterior thereof.

FIG. 14 is an enlarged fragmentary vertical cross-sectional view similarto FIG. 2, and illustrates another undercut interlocked junction betweena rounded peripheral edge of a glass sheet and an injection moldedencapsulation or frame, including the “flush-to-front” exterior thereof.

FIG. 15 is an enlarged fragmentary vertical cross-sectional view similarto FIG. 2, and illustrates another undercut interlocked junction betweena peripheral edge of a glass sheet having a rounded nose and aninjection molded encapsulation or frame, including the “flush-to-front”exterior thereof.

FIG. 16 is an enlarged fragmentary vertical cross-sectional view similarto FIG. 2, and illustrates another undercut interlocked junction betweena peripheral edge of a glass sheet having a continuously curved exteriorsurface portion and an injection molded encapsulation or frame,including the “flush-to-front” exterior thereof.

DESCRIPTION OF THE PREFERRED EMBODIMENT

An article of manufacture constructed in accordance with the method ofthe present invention is illustrated in FIGS. 1 and 2 of the drawingsand is generally designated by the reference numeral 10.

The article of manufacture 10 is specifically designed for utilizationas a computer screen or a computer glare filter, and includes a firstcomponent or glass sheet 11 and a second component in the form of aframe, encapsulation, border or border portion 12 injection molded frompolymeric/copolymeric synthetic plastic material, such as Santoprene®,PVC, crayton, polypropylene, or an equivalent material.

The glass sheet or first component 11 may have specific characteristicsassociated therewith which are created during fabrication dependingprimarily upon end use applications. For example, the glass sheet 11might have anti-glare characteristics, and preferably the glass istempered in a conventional manner. The glass sheet 11 includes a firstsurface 13 which in use is intended to be the front or outer surface andan opposite generally parallel rear or second surface 14. As is bestillustrated in FIG. 2, the surfaces 13, 14 merge with each other along aperipheral surface 15 which includes an angled surface 16 setting-offwith the glass sheet first surface 13 an included angle substantiallygreater than normal, such as 135°. The glass sheet 11 is normally cutfrom a larger sheet in a conventional manner and when thus cut, aterminal peripheral surface (not shown) is substantially normal to thesurfaces 13, 14. However, after the latter fabrication, the angledsurface 16 is formed by grinding the first surface 13 in a conventionalmanner. The ground angled surface 16 merges with the second surface 14at a peripheral terminal edge surface 17 which ranges in size between0.005 to 0.02 inch.

The second component, border, frame or encapsulation 12 substantiallycompletely and continuously peripherally encapsulates the peripheralsurface 15, the angled surface 16 thereof, the peripheral terminal edgesurface 17, and a peripheral surface area 18 of the second surface 14 ofthe glass sheet 11 which substantially underlies the angled groundsurface 16.

The encapsulation or frame 12 includes a first surface 23 opposite andparallel to a second surface 24 which merge with each other at aperipheral surface 25 which is substantially normal to the surfaces 23,24. It should be particularly noted that the surfaces 13, 23 of therespective glass sheet 11 and the frame, border or encapsulation 12 liein a common plane which corresponds to the exterior or outer side of theend use application, as in the case of a computer screen. Thus, in thisposition the surfaces 13, 23 define a “flush-to-front” aestheticappearance to the exterior of the computer screen 10.

The encapsulation or frame 12 also includes an inboard peripheralsurface 26 which is substantially parallel to the surface 25 andsurfaces 27, 28 and 29 which mirror the respective surfaces 18, 17 and15 of the sheet of glass 11. The surfaces 27 through 29 essentiallydefine an inwardly opening interlocking groove 19 which interlocks witha peripheral surface area of the glass sheet 11 through intimateengagement between the respective surfaces 18, 27; 17, 28 and 15, 29.Thus, the computer screen 10 not only presents a “flush-to-front”aesthetic appearance when in use, but the interlock achieved between theglass sheet 11 and the frame 12 is accomplished absent primer, bondingmaterial, intricate undercutting, multiple part fabrication and separateunification by sonic welding or the like.

The article 10 of FIGS. 1 and 2 is formed by injection molding theencapsulation or frame 12 along the periphery of the glass sheet 11 in amold 30 of FIGS. 3 through 7. The mold 30 includes an upper mold body 31and a lower mold body 32 which collectively define a mold cavity 33 whenthe mold bodies 31, 32 are closed in a conventional manner. Injectionports, sprues, runners, etc. are all conventional and are not shown inFIGS. 3 through 7 of the drawings.

The cavity 33 of the mold 30 includes respective cavity portions 34, 35defined by the respective mold bodies 31, 32.

The cavity portion 34 of the mold cavity 35 is of a generallyrectangular downwardly opening configuration. A first cavity portiondefining surface 36 which is substantially parallel to a second orparting surface 37 which defines a parting plane with a like partingsurface 40 of the mold body 32. A peripheral surface 38 merges thesurfaces 36, 37 and corresponds in size and shape to the peripheralsurface 25 of the encapsulation 12 (FIG. 2). The cavity portion 34 isthus a relatively shallow rectangular downwardly opening cavity.

The cavity portion 35 of the mold body 32 is defined by a first cavityportion defining surface 46 and opposite surfaces 47, 48 which aresubstantially in parallel relationship to each other. As viewed fromabove, the cavity portion 35 is of a substantially upwardly openingpolygonal channel-like configuration with the surfaces 47, 48 of themold body 32 corresponding to the eventually formed surfaces 26, 17,respectively, of the border, frame or encapsulation 12.

The glass sheet 11 (FIG. 4) is inserted between the mold bodies 31, 32when the latter are open in a conventional manner with the secondsurface 14 of the glass sheet 11 resting atop the parting surface 40 ofthe mold body 32. The peripheral edge 17 of the glass sheet 14 liesbetween the surfaces 47, 48 about the entirety of the cavity portion 35,and the peripheral edge 17 is spaced inboard from the surfaces 38, 48(FIG. 4).

The mold bodies 31, 32 are closed in the manner illustrated in FIG. 5.In the closed position, the glass sheet 11 is clamped between thesurfaces 36, 40, as is readily apparent in FIG. 5. Mold closingtechniques are conventional in the art, and suffice it to say that themold bodies 31, 32 are brought to the closed position of FIG. 5 suchthat a peripheral cavity portion 50 is defined by the surfaces 47, 46,48, 38, a peripherally outboard surface portion (unnumbered) of thesurface 36, and the surfaces 16, 17 and a portion (unnumbered) of thesurface 14 of the glass sheet 11 outboard of the surface 47. Acomparison between FIGS. 2 and 5 indicates the substantial identitybetween the cross-sectional configuration of the peripheral cavityportion 50 and the cross-sectional configuration of the encapsulation,frame or border 12 (FIG. 2) injection molded therein.

As is best illustrated in FIG. 6 of the drawings, syntheticpolymeric/copolymeric plastic material P is injected into the peripheralcavity portion 50 resulting in the formation of the encapsulation, frameor border 12 which forms the “flush-to-front” and interlockedconfiguration of the computer screen 10 heretofore described upon theeventual removal of the computer screen 10 being effected by the openingof the mold bodies 31, 32 in the manner illustrated in FIG. 7.Thereafter, the computer screen 10 can be raised upwardly, removed fromthe mold 30, and the process repeated.

Though the method of forming a unitized article 10 in the manner justdescribed is preferably associated with a computer screen or a computerglare filter or the like, other products are equally formed inaccordance with this invention, such as an article of manufacture 60 ofFIGS. 8 and 9 of the drawings which is a refrigerator “crisper” drawerdefined by an injection molded body 61 having an interior chamber 62 anda front wall 63 including a border or border portion 64 of a generallyrectangular or polygonal configuration. A handle 65 and oppositegenerally parallel side edges or sliders 66, 67 can be integrally moldedduring the injection molding of the article or drawer 60 to allow thedrawer to be mounted in sliding relationship with complementary sideslide rails of an associated refrigerator (not shown). A glass sheet 70is disposed in “flush-to-front,” interlocked injection moldedrelationship to the front wall 63 specifically in association with theborder portion or frame portion 64 thereof. The glass sheet 70 is of anidentical configuration to the glass sheet 11 of FIG. 2 and, thus, haslike primed numerals associated therewith to depict the identity of thecomponents.

As is best illustrated in FIGS. 10 and 11 of the drawings, a mold 80 isdefined by a male mold body 81 and a female mold body 82 whichcollectively define a mold cavity 83 when the mold bodies 81, 82 areclosed along respective parting line surfaces 87, 88. The parting linesurface 88 merges with a relatively flat surface 90 against which theglass sheet 70 is positioned and retained, by conventional vacuum, forexample, prior to the closing of the mold bodies 80, 82. When the moldbodies 81, 82 are closed, the cavity 83 thereof is a mirror image of thecross-section of the drawer illustrated in FIG. 10, and suitablepolymeric/copolymeric material is conventionally injected into thecavity 83 to form not only the entire drawer 60, but contemporaneouslytherewith achieving the interlock between the peripheral edge portion(unnumbered) of the glass sheet 70 and the border portion 64 of thefront wall 63.

The mold bodies 81, 82 are moved away from each other relativelyvertically, in the manner illustrated by the oppositely directed headedarrows associated therewith, resulting in the complete opening of themold bodies 81, 82 of the mold 80 and the subsequent removal of thedrawer 60 therefrom. As is best illustrated in FIGS. 9 and 12, therelationship between the peripheral edge of the glass sheet 70 and theencapsulated border portion or frame portion 64 of the front wall 63 isidentical to that of the glass sheet 11 and the border or frame 12 ofthe article 10 of FIGS. 1 and 2, namely, the two components are in“flush-to-front” interlocked injection-molded relationship to eachother.

In further accordance with this invention, another article ofmanufacture is illustrated in FIG. 13 of the drawings and is generallydesignated by the reference numeral 110.

The article of manufacture 110 is specifically designed for utilizationas a computer screen or a computer glare filter, just as in the case ofthe article of manufacture 10 of FIGS. 1 and 2. The major differencesbetween the two articles 10, 110 are that in the article 10 theperipheral surface 15 includes the angled surface 16 thereof (FIG. 2),whereas in the article 110, a peripheral edge 111 of a glass sheet 112is stepped by two peripheral surfaces 113, 114 which are normal to eachother and are also normal to a respective upper surface 115 and anoutboard peripheral surface 116 which merges with a lower surface 117.The surfaces 115, 117 of the glass 112 are parallel to each other and,of course, the surface 115 is flush with a surface 120 of a border,frame or encapsulation 125 having a groove 126 between peripheral legsor flanges 127, 128. The latter relationship serves to interlock thegroove 126 of the encapsulation 125 and the peripheral edge 111 of theglass sheet 112.

Another article of manufacture illustrated in FIG. 14 of the drawings isgenerally designated by the reference numeral 210.

The article of manufacture 210 includes a peripheral edge 211 which isdefined by a full curved outwardly convex peripheral surface 212 whichmerges with an upper surface 213 and with a lower surface 214. Thesurfaces 213, 214 are parallel to each other and the surface 213 isflush with a surface 215 of a border, frame or encapsulation 225. Theencapsulation 225 includes a groove 226 located between peripheral legsor flanges 227, 228. The latter relationship interlocks the peripheraledge 211 of the glass 220 with the groove 226 of the encapsulation 225.

Another article of manufacture is illustrated in FIG. 15 of the drawingsand is generally by the reference numeral 310. The article ofmanufacture 310 is essentially identical to the article of manufacture10 of FIG. 2 and has numerals identical to those appearing in FIG. 2,except primed to indicate identical structure/components thereof. Themajor difference between the articles 10, 310 resides in the glass sheet11′ of the article 310 having a peripheral terminal edge surface or nose17′ which is rounded, as compared to the flat peripheral surface 17 ofthe article 10 (FIG. 2). Furthermore, an angled surface 16′ of thearticle 310 defines a substantially lesser included angle with thesurface 14′ than the angle included by the surfaces 14, 16 of thearticle of manufacture 10. However, surfaces 13′, 23′ of the glass 11′and the encapsulation 12′, respectively, are flush to each other.

Another article of manufacture 410 of FIG. 16 is substantially identicalto the article of manufacture 310, except a surface 16″ thereof iscurved along an arc of constant radius between surfaces 13″ and 14″ withthe double primes being utilized to identify surfaces identical to thoseof the article of manufacture 310 of FIG. 14. The surface 13″ is alsoflush to a surface 23″ of an encapsulation or border 12″ of the article410.

Any one of the junctures illustrated in FIGS. 13 through 16 of thedrawings can, of course, be utilized in a drawer, such as the drawer 60of FIGS. 8 and 9 of the drawings, or comparable structure.

Although a preferred embodiment of the invention has been specificallyillustrated and described herein, it is to be understood that minorvariations may be made in the apparatus without departing from thespirit and scope of the invention, as defined the appended claims.

What is claimed is:
 1. A method of forming a unitized article whichincludes a border along a periphery of a glass sheet comprising thesteps of: (a) providing a glass sheet having first and second oppositesurfaces merging with each other along a peripheral surface whichincludes an angled surface setting-off with the glass sheet firstsurface an included angle substantially greater than normal, (b) placingthe glass sheet in a mold having opposing cavity portions whichcollectively define a cavity including a peripheral edge cavity portiondefined in part by a cavity defining surface which lies in the plane ofthe glass sheet first surface when the mold is closed, (c) closing themold such that the cavity defining surface and the glass sheet angledsurface set-off an angle complementary to said included angle and withthe glass sheet first surface abutting the cavity defining surfaceinboard of the angled surface, and (d) injecting hot synthetic plasticmaterial into the peripheral cavity portion to completely encapsulatethe glass sheet periphery by a synthetic plastic material border havinga first exterior surface coplanar with the glass sheet first surfacewhereby the latter two surfaces are flush and the glass sheet peripheryis in undercut interlocked relationship with the border.
 2. The methodas defined in claim 1 wherein the border has a second exterior surfacenon-coplanar to and spaced from the glass shelf second surface.
 3. Themethod as defined in claim 1 wherein the included angle is substantially135°.
 4. The method as defined in claim 1 including the step of grindingthe peripheral surface to form the angled surface thereof.
 5. The methodas defined in claim 1 wherein the angled surface and the glass sheetsecond surface merge at a peripheral terminal edge surface.
 6. Themethod as defined in claim 1 wherein the angled surface and the glasssheet second surface merge at a peripheral terminal edge surface rangingbetween 0.005 to 0.02 inch.
 7. The method as defined in claim 1 whereinthe unitized article is a flush-to-front computer screen.
 8. The methodas defined in claim 1 wherein the unitized article is a flush-to-frontwall of a drawer.
 9. The method as defined in claim 1 wherein the moldincludes at least two mold bodies having opposing contacting surfaces inthe closed position of the mold defining a parting line plane of themold, and the parting line plane is coplanar to the glass sheet secondsurface.
 10. The method as defined in claim 9 wherein the border has asecond exterior surface non-coplanar to and spaced from the glass shelfsecond surface.
 11. The method as defined in claim 9 wherein theincluded angle is substantially 135°.
 12. The method as defined in claim9 including the step of grinding the peripheral surface to form theangled surface thereof.
 13. The method as defined in claim 9 wherein theangled surface and the glass sheet second surface merge at a peripheralterminal edge surface.
 14. The method as defined in claim 9 wherein theangled surface and the glass sheet second surface merge at a peripheralterminal edge surface ranging between 0.005 to 0.02 inch.
 15. The methodas defined in claim 9 wherein the unitized article is a flush-to-frontcomputer screen.
 16. The method as defined in claim 9 wherein theunitized article is a flush-to-front wall of a drawer.
 17. The method asdefined in claim 1 wherein the border includes a peripheral edge inspaced relationship to at least a portion of the angled surface.
 18. Themethod as defined in claim 2 wherein the border includes a peripheraledge in spaced relationship to at least a portion of the angled surface.19. The method as defined in claim 9 wherein the border includes aperipheral edge in spaced relationship to at least a portion of theangled surface.
 20. The method as defined in claim 10 wherein the borderincludes a peripheral edge in spaced relationship to at least a portionof the angled surface.